Pivoting gripper

ABSTRACT

A pivoting gripper for a wire typing machine of the type which wraps wire from a coil around a package, twists the wire firmly to bind the package, and cuts the twisted wire from the coil. The pivoting gripper holds the free end of the wire from the coil during the twisting operation and includes a first and a second gripper jaw, each jaw having a face adapted to grip the free end of the wire. The first jaw is mounted in a gripper housing and moves alternately into and out of a gripper position with the second jaw intermediate the free end of the wire and the package. A pneumatic cylinder drives the first jaw into and out of the gripping position.

"United States Patent Inventor Robert W. Smith. Darlington. lnd. 3,196,779 7/1965 Embree 100/4 :52;- 8 1968 Primary Examiner-Billy J. Wilhite g Patented Jan. 2, 1971 v Attorney Allegrettl, Newnt & witcoff [73] Assignee Midstates Steel and Wire Company Crawfordsville, Ind. a corporation of Indiana [54] "VOTING GRIPPER ABSTRACT: A pivoting gripper for a wire tying machine of the type which wraps wire from a coil around a package, twists v 3 Claims, 4 Drawmg Figs. the wire firmly to bllld the package, and cuts the twisted wire U.S. from the coiL The pivofing gripper holds the free end of the f Cl B65) 13/23 wire from the coil during the twisting operation and includes a Fleld of Search and a second jaw each jaw having a face adapted 31; to grip the free end of the wire. The first jaw is mounted in a gripper housing and moves alternately into and out of a References Cmd gripper position with the second jaw intermediate the free end UNITED'STATES PATENTS of the wire and the package. A pneumatic cylinder drives the 2,982,199 5/1961 Jones 100/ 31X first jaw into and out of the gripping position.

I E i 1 22 t 36 o 44 i I 64 Q' I 3 I: 24 i I in 66 .1, I 5 560 These wire tying machines are used gripper means are not entirely-satisfactory! 7 proved wire tying machine.

' presentinvention will be more 3.0604 41 granted Oct. 30-, 1962 to P. A.' Vande'rbilt; U'.S.Pat. 'No. 3,179.03'8 granted Apr. 20, 196,510 .T.- B.(Macke nzie'and us. ramp. 3,251,296 grantediMay 17,1966 to R. W.Smith. n v 4 to bind packages. bundles ofnewspapersandthe like. i

. "Typically. in such a machine the stora e to be tied is moved along a conveyor onto a platform of the machine. A

FlG.- 2 is also a front view of the improved means for gripping with the gripper jaws withdrawn from a gripping position;

FIG. 3 is an exploded viewof the invention of the improved means for gripping; and i i v FIG. 4 is a perspective view of the improvement illustrated in FIG. 3.

DESCRIPTION OF THE' PREFERR EDEMBODIMENT I closed in the Smith patent, previously cited, embodiments of wire strand from a" coil is then made to encircle the package 7 releases the freeend of the wire while the end: of the wire attached tothe coil is-severc'gd. The bundle or package then advances, and the-next bundle or packageis positioned on the wiretyingmachine:j-.w-u A -1 1 I Typically the means forgrippingQ-thefree end of the wire loop or strandiincludes "a pairof jaws which mate to securely grasp the free endJOne; of. these jaws "is normally' positioned between the free end of the wire loopjand the package. This, however, has resulted in a problemi'Since the jaw remainsin intermediate. .positionbetween-the free end and 'the package, it holds the free end of the wire away from the package. Thus-after the-:twister twists the parallel runs together anddisengages from the twisted wirepermitting it to snap tightly "around .the package, .the"free end-of the wire catches on'the' gripper jaw and is bent away from the package. This outwardly 'bent ..end :clogs' machines and damages packages: and bundles. It also creates 'a source=of injury to those handling the packages'or bundlesl 'ln'short, prior-art S MMARY or. rnel vENIloN. In a principal aspect, thepresent invention comprises an im-- proved means for gripping theyfreejend'of a. wire which is being twisted about a package by a wire tying machine. Includedin the means for gripping a gripper jaw positioned betweenthe wire end andthe package'Thejaw is adapted to pivot andallow the free end of the wire tofbe released by the twister means disengage the twisted wire. I i

it is thus an object of the present invention toprovide an im- It is a further object of the present invention to provide im proved means for gripping the free end of wire in a wire tying improvement which is the invention.

the invention may be used with any similar wire tying device.

Further, because wiretyingmachines, such as disclosed by Smith, are well known in the art,'the entire wire tying machine is not shown in the drawings. Rather the drawings illustrate the Referring to FIGS. 1 and 2, typically in a'wire tying machine a package 10 is positioned in the machine so that a loop or strand of wire 12 unwinding from a coil 14 may be passed under and around the package 10. The strand [2 of wire thus makes two parallel ruhs beneath the package 10 with one run terminating as a free end 16 and the other-end extending to thecoil l4. i Y

The free end 16 is then grasped between gripper means 17 i and the wire from the coil )4 is tightened about the package 10. Twister means 18 then engage the parallelruns of wire beneath the package lfl'andtwist thoseruns together. While the twisting operation takesplace, the free end 16 of the wire is maintained in a gripped position.

releases the freeend l6v of the wire. In prior art devices this easily besynchronized with the ,operation'of the twisting means of the wire tying machine.

A further object of the presentinvention is to provide an improved means for gripping which maybe. easily. incorporated withpresently. designed and manufactured wire tying machines.

These andother description whichfollowsz "FlG.,l is a frontview of the improved meansfor gripping in: s p i sv i i objects, advantages and features of the fully-setgforth-in the detailed V.

release was not entirely effective. because a part of the gripper means 17 would remain between or .intermediate the free end 16 of the wire and the package I O-causing the free end 16 to bend away from the .package after being released by the twister 18. The present invention provides gripper means 17 1 which moves completely out of the path of thewire end 16' permitting the end 16 to snapcleanly 'againstthe -package'.l0

along with the remainder of the twisteclstrand or loop 12.

FIGS. 3 and 4 illustrate in greater detail the. improved gripper means. included is an upper. gripperjaw22 having a gripper face 24, a lower gripperjaw 26 havinga gripper face 28.and a gripper housing 30. The vupper gripper jaw 22 includes an extended mounting arm 32 which'i's adapted to slidably engage a slot- 34 inhousing30. Arm 32 is pivotally mounted in slot 34 by means of a shoulderscrew 36.

Threadably inserted in a screw opening 38 in the head of upper gripper jaw 22'is an eyepin 40. A pneumatic cylinder-42 having an extendable piston rod 44 attached to'a bracket 46 is connected with the eyepin 40. The opposite end of :the a cylinder 42 is pivotally mounted in a tixedblock 48. Block 48 is, in turn, attached to a gripper housing-platform 50LThus;

' when piston rod 44 withdraws within cylinder 42, the upper jaw 22' rotates about the axis of shoulder screw 36 and is withdrawn from a position where jaw 22 may cooperate with jaw 26. Extending the piston rod from cylinder 42 drives the jaw 22 into a position where it can cooperate lower jaw 261 Lower jaw 26 is slidably positioned ina vertical channel 52 I defined in the housing 30. Lower jaw 26 is normallybiased in a retracted gripper position by'aspring 5 4 cooperating with a washer and pin 58; A jaw extension 60 of the jaw 26 engages an integral forward crossmember 62 of housing 30 which also I serves to define part of the vertical channel 52.

A plate 64 attached to housing 30 by'means of machine screws 66 and 67 prevents lower jaw 26 from becoming'disen-s gagedfrom the channel SZLThe plate 64includes-an upper wire guide surface 70 which guides the incoming run of an end as at 14 in H05. 1 and 2 passes under the package is guided over the surface 70 of the plate 64, passes upwardly around the package 10 and back down and under the package 10.

The end 16 of the wire then passes between the gripper jaws 22 and 26 and more particularly between surfaces 24 of jaw 22 and 28 of jaw 26. At this point upper gripper jaw has been rotated in the direction of the arrow. in'FlG. 4 so as to be appropriately in position to engage the end 16 of the wire in cooperation with lower jaw 26. Lower jaw 26 is then driven upward against the force of the spring 54. The means for driving the lower jaw 26 upward are well known in the art and therefore not illustrated. The end 16 of the wire is engaged between the jaws and the coil 14 is reversed so as to tightly draw the strand 12 about the package 10. The twister means then advances into engagement with the, parallel runs of wire beneath the package 10 and twist these runs in the manner previously described.

The twister means then retracts from engagement with the twisted wire. Simultaneously, the upper jaw 22 is withdrawn from engagement with the end 16 of the wire in response to the action of the cylinder 42 in the direction opposite that of the arrow shown in FIG. 4. At the same time, of course, the lower jaw 26 retracts to the position illustrated in FIG. 4 which is limited by the jaw extension 60 and crossmember 62. The sequence of operation is then repeated for the next package which enters the wire tying machine.

Although a single pair of jaws have been illustrated for gripping the end of a wire strand, the present invention is operable to provide similar results with any arrangement of gripper jaws. The important feature of the invention is the removal of the jaw or any portion of a jaw from a position intermediate the end of the wire strand and the package subsequent to the twisting operation. This eliminates the problem of bending an end of the wire away from the package.

lclaim:

1. In a wire tying machine of the type which passes a wire loop around a package on a platform, said wire having opposite ends which make parallel runs, at least one of said ends being free, said machine including twister means to twist said wires together, the improvement comprising in combination:

means for gripping said free end'of wire, said means including at least two jaws;

one of said jaws being a lower jaw substantially perpendicular to said parallel runs of wire;

the other of said jaws being an intermediate jaw pivotally mounted in a plane substantially parallel to said parallel runs of wire and movable between a retracted position and a gripping position, said intermediate jaw being intermediate said package and said free end of wire when in said gripping position;

said intermediate jaw cooperable with said lower jaw for gripping said free end of wire in said gripping position; and

driving means for pivotally moving said intermediate jaw between said gripping position and said retracted positiOn. l I

2. The improvement in claim 1 wherein said driving means include a pressure responsive cylinder pivotally connected to said intermediate jaw.

3. In a wire tying machine of the type which passes a wire loop around a package on a platform, said wire having opposite ends which make parallel runs, at least one of said ends being free, said machine including twister means to twist said wires together, the improvement comprising, in combination: means for gripping said fgree wire end, said means including at least two jaws, one of said jaws positioned intermediate said package and said free wire end while said free wire end is being gripped between said intermediate jaw and the other jaw, means for removing said intermediate jaw from position between said package and said free wire end. said means for removing including driving means, said driving means including a pressure responsive cylinder pivotally connected at one end to said intermediate jaw and fixed at its opposite end. 

1. In a wire tying machine of the type which passes a wire loop around a package on a platform, said wire having opposite ends which make parallel runs, at least one of said ends being free, said machine including twister means to twist said wires together, the improvement comprising in combination: means for gripping said free end of wire, said means including at least two jaws; one of said jaws being a lower jaw substantially perpendicular to said parallel runs of wire; the other of said jaws being an intermediate jaw pivotally mounted in a plane substantially parallel to said parallel runs of wire and movable between a retracted position and a gripping position, said intermediate jaw being intermediate said package and said free end of wire when in said gripping position; said intermediate jaw cooperable with said lower jaw for gripping said free end of wire in said gripping position; and driving means for pivotally moving said intermediate jaw between said gripping position and said retracted position.
 2. The improvement in claim 1 wherein said driving means inclUde a pressure responsive cylinder pivotally connected to said intermediate jaw.
 3. In a wire tying machine of the type which passes a wire loop around a package on a platform, said wire having opposite ends which make parallel runs, at least one of said ends being free, said machine including twister means to twist said wires together, the improvement comprising, in combination: means for gripping said free wire end, said means including at least two jaws, one of said jaws positioned intermediate said package and said free wire end while said free wire end is being gripped between said intermediate jaw and the other jaw, means for removing said intermediate jaw from position between said package and said free wire end, said means for removing including driving means, said driving means including a pressure responsive cylinder pivotally connected at one end to said intermediate jaw and fixed at its opposite end. 